import java.util.Scanner;
public class Test {
    public static void main(String[] args) {
        Scanner scanner=new Scanner(System.in);
        int n=scanner.nextInt();
        int flg=1;
        for(int i=2;i<n;i++){
            if(n%i==0){
                flg=0;
                break;
            }
        }
        if(flg==1){
            System.out.println(n+"是素数");
        }
        else {
            System.out.println(n+"不是素数");
        }
    }
}
